<?
class DES 
 { 
 	var $key; 
 	var $iv; //偏移量 
 	 
 	function __construct( $key, $iv=0 ) { 
 	//key长度8例如:1234abcd 
 		$this->key = $key; 
 		if( $iv == 0 ) { 
 			$this->iv = $key; //默认以$key 作为 iv 
 		} else { 
 			$this->iv = $iv; //mcrypt_create_iv ( mcrypt_get_block_size (MCRYPT_DES, MCRYPT_MODE_CBC), MCRYPT_DEV_RANDOM ); 
 		} 
 	} 
 	 
 	function encrypt($str) { 
 	//加密，返回大写十六进制字符串   /base64_encode 
 		$size = mcrypt_get_block_size ( MCRYPT_DES, MCRYPT_MODE_CBC ); 
 		$str = $this->pkcs5Pad ( $str, $size ); 
 		return strtoupper( bin2hex( mcrypt_cbc(MCRYPT_DES, $this->key, $str, MCRYPT_ENCRYPT, $this->iv ) ) ); 
 	} 
 	 
 	function decrypt($str) { 
 	//解密 
 		$strBin = $this->hex2bin( strtolower( $str ) ); 
 		$str = mcrypt_cbc( MCRYPT_DES, $this->key, $strBin, MCRYPT_DECRYPT, $this->iv ); 
 		$str = $this->pkcs5Unpad( $str ); 
 		return $str; 
 	} 
 	 
 	function hex2bin($hexData) { 
 		$binData = ""; 
 		for($i = 0; $i  < strlen ( $hexData ); $i += 2) { 
 			$binData .= chr ( hexdec ( substr ( $hexData, $i, 2 ) ) ); 
 		} 
 		return $binData; 
 	} 
  
 	function pkcs5Pad($text, $blocksize) { 
 		$pad = $blocksize - (strlen ( $text ) % $blocksize); 
 		return $text . str_repeat ( chr ( $pad ), $pad ); 
 	} 
 	 
 	function pkcs5Unpad($text) { 
 		$pad = ord ( $text {strlen ( $text ) - 1} ); 
 		if ($pad > strlen ( $text )) 
 			return false; 
 		if (strspn ( $text, chr ( $pad ), strlen ( $text ) - $pad ) != $pad) 
 			return false; 
 		return substr ( $text, 0, - 1 * $pad ); 
 	} 
 	 
 } 
//         $desobj = new DES('8765432');
//        $xml = $desobj->encrypt('1234567');
//        
//        $dd = $desobj->decrypt($xml);
//        
//        
//        $dd='';
 ?>